422 Key to the System of 



calyx-lobe short-pointed from between the summit of the 

 adherent petals ; lower calyx-lobes upwards very narrow, 

 much pointed, reaching across and somewhat beyond the 

 upper ; labellum glabrous, gradually much narrowed up- 

 wards, its basal appendage brush-like ; upper angle of 

 the gynostemium-appendages ending in a minute pointed 

 lobule ; fruit rather slender. P. acuminata. 



Labellum hardly pointed or quite blunt ... ... 1816 



1816. Lower calyx-lobes almost or quite surpassed by the 



upper, their free portion separated by a wide sinus. 



Often somewhat tall ; basal leaves from lancelolar- to 

 orbicular-ovate ; stem -leaves one or two, bract-like ; 

 flower large, its stalklets soon elongated ; upper calyx- 

 lobe hardly pointed or somewhat blunt, about as long as 

 the lower or somewhat longer ; labellum linear-elliptical, 

 glabrous, its basal appendage brush-like ; upper lobule 

 of the gynostemium-appendages very narrow and acute, 

 the lower broadish, blunt and ciliolated ; fruit rather 

 slender. P. curta. 



Lower calyx-lobes considerably surpassing the upper, 

 their free portion separated by a rather narrow sinus. 



Seldom tall ; basal leaves from lanceolar- to roundish-ovate ; 

 stem-leaves one or two, clasping, almost bract-like ; 

 flower of moderate size, on a long stalklet, often ante- 

 riorely somewhat reddish ; upper calyx-lobes simply acute ; 

 lower calyx-lobes almost setular upwards ; labellum lan- 

 ceolar -elliptical, glabrous, its basal appendage somewhat 

 brush-like; both angles of the gynostemium-appendages 

 pointed, more acutely the upper ; fruit rather slender. 



P. peduncnlata. 



HYDRO CH ABIDE AE. 



OTTELIA. 



1817. Leaves mostly floating, very firm, from narrow- 



elliptical to broad-ovate. 



Leaves somewhat succulent, their venulation reticular ; 

 flowers rather large, but of two sizes, those with smaller 



Eetals more copiously seed -bearing ; involucre and calyx 

 rm ; petals upwards white ; fruit nearly ovate ; seeds 

 ellipsoid. Figure 115. O. ovalifolia. 



